A RULEBASE PHYSIOGRAPHIC CHARACTERIZATION OF A DROUGHT PRONE WATERSHED APPLYING REMOTE SENSING AND GIS

Efficient micro-watershed management needs characterization of it to optimize natural resources, which is especially important in drought prone areas. In the present study micro-watersheds of Gandheshwari tributary in Chotta-Nagpur Plateau are characterized based on physiographic properties towards agricultural potentiality. An algorithm interpolating elevation values using an empirical formula is proposed to obtain an improved Digital Elevation Model (DEM). IRS LISS-III Satellite data is used to acquire important parameters like landuse/landcover and drainage. Image processing techniques like edge enhancement, edge detection, and principal components analysis are used for improving lineament detection. For characterization of watershed landform analysis using physiographic parameters is done in Geographic Information System (GIS). Detailed drainage network obtained from satellite image, the improved DEM and other GIS layers of land based information are used to delineate micro-watersheds. The Agricultural Hydrologic Response Units (AHRU) targeting agricultural use of the land are derived by overlaying the delineated parameters and are grouped into thirty response units based on their agricultural potential. Micro-watersheds are characterized based on the dominant AHRU giving spatial information about agricultural suitability, emphasizing availability and scarcity of water so that respective water conservation practices can be improved to use the potential AHRU